Cutting and shaping tool

ABSTRACT

A cutting tool especially for difficult accessible structures of materials such as steel, concrete, reinforced materials, carried preferably on and operated by a remote controlled vehicle, where the cutting tool comprises a C-shaped frame ( 1 ), the end of the first arm of the frame ( 1 ) comprising a rotation device ( 4 ), the end of the second arm comprising a mounting device ( 7 ), the rotation device ( 4 ) and the mounting device ( 7 ) being adapted to receive one end of a milling shaft ( 3 ) each, and to rotate the milling shaft ( 3 ) during operation, the frame ( 1 ) thereby being displaced towards the structure ( 5 ) one arm of which at each side of the structure, by a feeding mechanism ( 9 ) secured to an operating arm ( 8 ) on the vehicle.

The present invention is related to a cutting tool for especiallydifficult accessible structures of materials such as steel, concrete,reinforced materials.

In many cases steel structures are dismantled or parts are to bereplaced, resulting in sections or parts of the structures be cut away.In many cases such cutting may be difficult due to bad accessibility andthe environment under which the work has to be performed. Structures inthe sea or at the sea bottom, in nuclear plants etc. are examples ofsuch works which requires special skill and equipment to be performed.

It is essential that equipment used in such cases is flexible and easyto manoeuvre and operate. In cases where parts are to be cut away to bereplaced, it is also essential that the cutting surfaces can be usedmore or less without further treatment, such as by welding. It isfurther an advantage that the equipment is able to cut severaldimensions without having to replace the equipment or make essentialmodification on the equipment.

It is well known to use wires covered with diamonds to saw suchstructures by means of a cutting tool carried by a remote controlledvehicle. Even if such equipments ensure that the wire is kept tight,there are disadvantages connected with the principle of sawing by meansof wires, especially in connection with the accuracy of the cuts as wellas the space necessary for operating the vehicle with the cutting tool.

With the cutting tool according to the present invention, the aboverequirements are fulfilled and disadvantages by known method andequipment are avoided. This is achieved with the cutting tool accordingto the present invention as defined by the features stated in theclaims.

The drawing discloses in

FIG. 1 schematically a ground plan of a cutting equipment in positionagainst a structure to be cut and

FIG. 2 discloses a front view of one embodiment of a milling shaft.

The cutting tool according to the present invention is suitably mountedon a remote operated vehicle, enabling the cutting tool to operate inthe sea, at the sea bottom as well as at difficult accessible places atsea or offshore, as well as in environments such as nuclear plants andenvironments with risk for explosion etc.

An operating arm 8 is mounted on the remote operated vehicle, adapted tobe manoeuvred in all directions.

At the end of the operating arm 8, is located a connection frame 2 whichcan be displaced axially by an extension means, such as a feedingmechanism 9.

To the connection frame 2 is secured a support frame 1, the connectionbetween the support frame 1 and the connection frame 2 enabling thesupport frame to be rotated to a desired position such as vertically,horizontally etc.

The support frame 1 has a C-shape, comprising two arms extending fromthe connection frame 2. The distance between the two arms decides themaximum dimension, such as diameter, of the structures to be cut. Thedistance between the two alms may be in the range of 0.5 or 1.5 m orlarger.

At the end of one arm of the support frame 1, a rotation device 4 issecured, at the end of the other arm is secured a mounting device 7, amilling shaft 3 extending from the rotation device 4 to the mountingdevice 7.

The shape and surface of the milling shaft 3 may be chosen as being wellsuited for machining a structure of a material or a combination ofmaterials in question. As such the milling shaft may be a solid rodprovided with a surface adapted for machining respectively grinding ofthe structure.

The milling shaft 3 may be a solid and strong rod having minimumdiameter related to the structure to be cut. The milling shaft 3 maycomprise along the machining zone at least one grinding surface on atleast parts of the shaft surface, said grinding surface(s) may compriseembedded diamonds, at least one helically shaped grinding surface,several spaced apart rings with grinding surfaces or such. Rings asmentioned may be connected with and captured by the milling shaft coreby non-circular cross section of the ring interior and correspondingcross section of the core exterior, or other suitable means. The activegrinding surface or surfaces of the milling shaft 3 may be easilyreplaceable, as may the milling shaft 3 as such.

One embodiment of a milling shaft 3 is disclosed in FIG. 2 and comprisesone helically extending milling surface covered with artificialdiamonds. By rotating the milling shaft 3 and activating the feedingmechanism 9, the milling shaft 3 will cut or grind into the structure 5,leaving a cutting surface which is smooth and straight. The forces fromthe milling shaft 3 to the structure 5 are very small, resulting also insmall forces to be transferred from the milling shaft 3 to the remotecontrolled vehicle via the support frame 1.

To increase the efficiency of the cutting tool according to the presentinvention, the arms are provided with oscillating devices 6, providingthe milling shaft 3 with a reciprocating movement in the axial directionof the shaft 3 in addition to the rotation. The oscillating displacementensures that material from the milling operation is taken out of thecutting area and avoiding that the same spot of the milling shaft isexposed to abrasion over a too long period of time.

The securement of the milling shaft 3 to the rotation device 4respectively the mounting device 7 is adapted for automatic replacementof the milling shaft 3 as the consumable tool, to ensure continuousoperation, which is especially beneficial when operating the remoteoperated vehicle and the cutting tool at locations with limited orrestricted access.

1. A cutting tool especially for difficult accessible structures ofmaterials such as steel, concrete, reinforced materials, carriedpreferably on and operated by a remote controlled vehicle, wherein thecutting tool comprises a C-shaped frame (1), the end of the first arm ofthe frame (1) comprising a rotation device (4), the end of the secondarm comprising a mounting device (7), the rotation device (4) and themounting device (7) being adapted to receive one end of a milling shaft(3) each, and to rotate the milling shaft (3) during operation, theframe (1) thereby being displaced towards the structure (5) one arm ofwhich at each side of the structure, by a feeding mechanism (9) securedto an operating arm (8) on the vehicle.
 2. Cutting tool according toclaim 1, wherein the arms being provided with oscillating devices (6)reciprocation the rotating milling shaft (3).
 3. Cutting tool accordingto claim 1, wherein the milling shaft (3) comprises at least along themachining zone at least one grinding surface on at least parts of theshaft surface, said grinding surface(s) may comprise embedded diamonds,a helically shaped grinding surface, several spaced apart rings withgrinding surfaces.
 4. Cutting tool according to claim 2, wherein themilling shaft (3) comprises at least along the machining zone at leastone grinding surface on at least parts of the shaft surface, saidgrinding surface(s) may comprise embedded diamonds, a helically shapedgrinding surface, several spaced apart rings with grinding surfaces.